For the third time in three months, a declassified Defense Department video shows U.S. Navy F-18 fighters seemingly encountering UFOs.

"Oh my gosh, dude," said one pilot in the video of their F/A-18 Super Hornet military jet's 2015 encounter with the unusual object along the East Coast. The oval-shaped aircraft zipped with befuddling speed.

"Wow! What is that, man?" said another. "Look at that flying!"

The 35-second video, released by the privately owned media and scientific research company To the Stars Academy of Arts and Science, is the latest to suggest the existence of hovering egg-shaped vessels since the Pentagon in December publicly acknowledged a program dedicated to the study of unidentified flying objects. While the Advanced Aviation Threat Identification Program ran from 2007 to 2012, those familiar with it say efforts are still made to further learn about these objects.

News of the mystery program and the first two declassified videos of the strange objects introduced the possibility of extraterrestrial aircraft for the first time since the Air Force's Project Blue Book, records cataloguing more than 12,000 UFO sightings between 1947 and 1969, when the program was shut down. The program was unable to find "any technological developments or principles beyond the range of present-day scientific knowledge," and "no evidence indicating that sightings categorized as 'unidentified' are extraterrestrial vehicles," according to the Air Force.

The release of the videos was quietly arranged by intelligence officer Luis Elizondo, who headed the Advanced Aviation Threat Identification Program and left the Defense Department late last year. He told The Washington Post's Joby Warrick in December that the raw footage from encounters between fighter jets and "anomalous aerial vehicles," which is what the military calls UFOs, could help educate pilots and advance aviation safety.

But Elizondo also wanted to raise attention to a little-known phenomenon that could pose "potential security threat."

As Warrick reported:

"Neither the Pentagon nor any of the program's managers have claimed conclusive proof of extraterrestrial visitors, but Elizondo, citing accounts and data collected by his office over a decade, argues that the videos and other evidence failed to generate the kind of high-level attention he believes is warranted. As part of his decision to leave the Pentagon, he not only sought the release of videos but also penned a letter to Defense Secretary Jim Mattis complaining that a potential security threat was being ignored."

One of the videos released in December is of former U.S. Navy pilot Cmdr. David Fravor's 2004 encounter with a flying object about the size of his plane moving at a rapid pace, unlike anything else he'd seen in the air. He told The Post's Eli Rosenberg that he has not forgotten the incident. As Rosenberg reported:

"An order came in for [Fravor] to suspend the exercise and do some 'real-world tasking,' about 60 miles west of their location, Fravor said. He said he was told by the command that there were some unidentified flying objects descending from 80,000 feet to 20,000 feet and disappearing; he said officials told him they had been tracking a couple dozen of these objects for a few weeks.

"When they arrived closer to the point, they saw the object, flying around a patch of white water in the ocean below.

" 'A white Tic Tac, about the same size as a Hornet, 40 feet long with no wings,' Fravor described. 'Just hanging close to the water.'

The object created no rotor wash – the visible air turbulence left by the blades of a helicopter – he said, and began to mirror the pilots as they pursued it, before it vanished.

" 'As I get closer, as my nose is starting to pull back up, it accelerates and it's gone,' " he said. 'Faster than I'd ever seen anything in my life. We turn around, say let's go see what's in the water and there's nothing. Just blue water.' "

To this day, 13 years later, Fravor is certain about one thing: That the object is "something not from the Earth," he said.